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<h2>How To Change The Processor Clock...</h2>
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<p>The MSP430 was designed to power-up quickly from low-power mode without
having to wait a long time for the clock to settle.
The Digitally Controlled Oscillator (DCO) of the MSP430F2274 is an accurate
and stable clock that becomes active from low-power mode in
in 1-2us, without any erratic pulses.

<p>The frequency of the DCO is accurate to 1-2% and can be controlled by
setting bits in the module's <b>BCSCTL1</b> and <b>DC0CTL</b> registers.
The MSP430 has calibrated frequencies of 1, 8, 12, and 16 MHz as follows:

<blockquote><pre>CALDCO_16MHZ = 0x10F8;
CALBC1_16MHZ = 0x10F9;
CALDCO_12MHZ = 0x10FA;
CALBC1_12MHZ = 0x10FB;
CALDCO_8MHZ  = 0x10FC;
CALBC1_8MHZ  = 0x10FD;
CALDCO_1MHZ  = 0x10FE;
CALBC1_1MHZ  = 0x10FF;</pre></blockquote>

<p>Thus, to change the speed of the MSP430, set the selected speed values
in the <b>BCSCTL1</b> and <b>DC0CTL</b> registers:

<blockquote><pre>;    MSP430 Clock - Set DCO to 12 MHz:
     mov.b   &CALBC1_12MHZ,&BCSCTL1     ; Set range
     mov.b   &CALDCO_12MHZ,&DCOCTL      ; Set DCO step + modulation</pre></blockquote>

<p>See MMB pages 167-170.
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